13043478 Bellefleur, Gilles (Geological Survey of Canada, Canada); Riedel, Michael and Brent, Tom. Seismic and well-log inference of gas-hydrate accumulations on Richards Island, Northwest Territories, Canada: in Arctic/ATC (Goodway, William, prefacer; et al.), Leading Edge (Tulsa, OK), 32(5), p. 556-563, illus. incl. sect., sketch map, 13 ref., May 2013.

The Mackenzie Delta in Canada's Northwest Territories hosts many permafrost-related gas-hydrate accumulations that were indirectly discovered or inferred from conventional hydrocarbon exploration programs. In particular, gas-hydrate intervals characterized with high saturation show high resistivity and high P- and S-wave velocity on well-log data, and are typically found in sand-rich horizons. The acoustic impedance contrast between nonhydrate and hydrate-bearing sediments usually produces strong amplitude reflections on seismic data. Such a signature was previously observed onshore at Mallik, Northwestern Territories (Collett et al., 1999), and on the North Slope of Alaska (Collett et al., 2011). Here, we use 2D and 3D seismic reflection data acquired by industry on Richards Island to map and characterize gas-hydrate accumulations beneath a thick permafrost area of the Mackenzie Delta (Figure 1). Specifically, we show new seismic evidences of gas-hydrate accumulations above the Ya Ya and Umiak conventional gas fields.

DOI: 10.1190/tle32050556.1

13044148 Waroszewski, Jaroslaw (Wroclaw University of Environmental and Life Sciences, Institute of Soil Science and Environmental Protection, Wroclaw, Poland); Kalinski, Krzysztof; Malkiewicz, Malgorzata; Mazurek, Ryszard; Kozlowski, Grzegorz and Kabala, Cezary. Pleistocene-Holocene cover-beds on granite regolith as parent material for Podzols; an example from the Sudeten Mountains: Catena (Giessen), 104, p. 161-173, illus. incl. 5 tables, sketch map, 71 ref., May 2013.

Pleistocene periglacial cover-beds have been considered to be the proper parent material of soils in the medium mountains of Central Europe and in other areas influenced by the periglacial conditions. The concept highlights an importance of solifluction and cryoturbation phenomena, and an addition of aeolian silt (loess) in the formation of cover-beds. Significant loess admixture may, however, hinder podzolization process. The objective of the present study was to recognize the stratification of slope materials in the upper zone (1000-1200m ASL) of the Sudeten Mts. (SW Poland) and its relation to the morphology and properties of Podzols. Mineralogical and submicromorphological analyses confirmed autochthonous origin of the parent materials and excluded loess admixture. Macro- and micro-observations proved periglacial formation of deeper beds, while the pollen analysis confirmed the Holocene age of an uppermost sand layer. Finally, four-partial mineral sequences were distinguished in soil profiles: (1) an underlying granite regolith (not always present within the standard soil pit), (2) a basal periglacial layer formed by solifluction, (3) a cryoturbated transitional zone instead of typical intermediate periglacial layer, (4) an uppermost sandy (or a sandy-silty) layer instead of the upper periglacial layer. Modification of periglacial cover-bed series by replacing of the silty "upper periglacial layer" with sandy Holocene cover allowed Podzol formation under favorable climate conditions. The same palynological and micromorphological observations confirmed polygenetic nature of Podzols. The present-day Bh horizon is in fact a humus layer of a late Pleistocene-early Holocene brown earth buried under a sandy cover. An albic horizon thickness and its lower boundary are therefore related to the lithological discontinuity in the cover-bed series. Abstract Copyright (2013) Elsevier, B.V.

DOI: 10.1016/j.catena.2012.11.006

13041195 Beilke, A. J. (University of Wisconsin at Madison, Department of Soil Science, Madison, WI) and Bockheim, J. G. Carbon and nitrogen trends in soil chronosequences of the Transantarctic Mountains: Geoderma, 197-198, p. 117-125, illus. incl. 3 tables, sketch map, 47 ref., April 2013.

Determination of carbon and nitrogen levels in soils of ice-free areas of the Transantarctic Mountains, along with their origin, may determine whether these soils serve as a source or sink of carbon with an increasingly warmer climate. Organic and inorganic forms of carbon and nitrogen were measured in five soil chronosequences in the Transantarctic Mountains using flash combustion and spectrometry. Accumulation of coal carbon was significant in the Beardmore Glacier area and was quantified using chemi-thermal oxidation followed by flash combustion. Carbon levels decreased with drift age for two of the sequences. Decreases in carbon in the Hatherton Glacier sequence were due primarily to high levels of carbon in young ice-cored drifts. Carbon content increased with drift age for the Beardmore Glacier sequence due to the presence of coal in older drifts. Nitrogen content increased with age for a majority of the soil chronosequences. Inorganic carbon and all forms of nitrogen were significantly and positively correlated with mean annual precipitation. Our results suggest that carbon levels in similar settings do not significantly change over time; changes in temperature or moisture associated with microclimate likely play a much larger role in carbon and nitrogen levels. Abstract Copyright (2013) Elsevier, B.V.

DOI: 10.1016/j.geoderma.2013.01.004

13043152 Clague, John J. (Simon Fraser University, Centre for Natural Hazard Research, Burnaby, BC, Canada). Cryospheric hazards: Geology Today, 29(2), p. 73-79, illus., 10 ref., April 2013.

Glaciers are an important element of the Earth system. Glaciers provide numerous, though poorly appreciated, ecological and economic benefits. However, glacial processes can also be hazards. Local glacial hazards include catastrophic floods from lakes impounded by glaciers and their moraines, landslides and debris flows induced by glacier thinning and retreat and permafrost thaw, and enhanced seismicity and volcanism due to large-scale deglaciation. Regionally, rivers can be affected by changes in sediment supply from glacier forefields. Perhaps the greatest hazard that glaciers pose on a global scale of coastal erosion and flooding caused by sea-level rise. If Earth's climate continues to warm, as scientists forecast, the rate of sea-level rise will increase and some low-lying coastal areas will be flooded by the end of this century. Abstract Copyright (2013), Blackwell Publishing Ltd, The Geologists' Association & The Geological Society of London.

DOI: 10.1111/gto.12005

13041378 Eckerstorfer, Markus (University Centre, Arctic Geology Department, Longyearbyen, Norway); Christiansen, Hanne H.; Vogel, Stephan and Rubensdotter, Lena. Snow cornice dynamics as a control on plateau edge erosion in central Svalbard: Earth Surface Processes and Landforms, 38(5), p. 466-476, illus. incl. geol. sketch map, 54 ref., April 2013.

Snow cornices grow extensively on leeward edges of plateau mountains in central Svalbard. A dominant wind direction, a snowdrift source area and a sharp slope transition largely control the formation of snow cornices in a barren peri-glacial landscape. Seasonal snow cornice dynamics control bedrock weathering and erosion in sedimentary bedrock on the Gruvefjellet plateau edge in the valley Longyeardalen. Air, snow and ground temperature sensors, as well as automatic time-lapse cameras on a leeward facing plateau edge were used to study seasonal cornice dynamics. These techniques allowed for monitoring of cornice accretion, deformation and collapse/melting in great detail. The active layer of the top plateau edge is characterized by high moisture content due to rain before freeze-up in autumn and cornice meltdown during spring thaw. Thus frost weathering there can be very efficient in this otherwise cold and dry environment. Within the first autumn snowstorms, a vertical fully developed cornice was in place (190 cm thick). The backwall surface beneath the thickest part of the cornice remained in the ice segregation 'frost cracking window' for almost nine months. Highly weathered rock material from the plateau edge is thus incorporated into the cornice during cornice accretion. Brittle snow deformation leads to the opening of cornice tension cracks between the cornice mass and the snowpack on the plateau. These cracks are a prerequisite for cornice collapses, and often trigger cornice fall avalanches on the slope beneath. In these open cornice tension cracks, weathered rock debris, plucked from the plateau edge, can be visible, demonstrating the erosional property of the cornices. The cornice will either collapse or melt, resulting in suspended sediment transport downslope by cornice fall avalanche or release as rock fall respectively. Therefore, cornices both promote and trigger high weathering rates on Gruvefjellet, and thus control presently the development of the rockwall free faces and the talus cones. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/esp.3292

13036613 Ballantyne, Colin K. (University of Saint Andrews, School of Geography and Geosciences, St. Andrews, United Kingdom). A 35-year record of solifluction in a maritime periglacial environment: Permafrost and Periglacial Processes, 24(1), p. 56-66, illus. incl. 2 tables, sketch map, 30 ref., March 2013.

Eight segmented PVC columns (Rudberg pillars) inserted vertically in the treads of three vegetation-covered ('turf-banked') solifluction lobes at altitudes of 912-1031 m in the Fannich Mountains of NW Scotland were exhumed 35 years after insertion, and downslope displacement of each segment was measured to derive velocity profiles for each site. Data from these profiles yielded average surface velocities of 7.8-10.6 mm a^-1 (mean 8.8 mm a^-1), average volumetric velocities of 8.3-13.3 cm³ cm^-1 a^-1 (mean 10.5 cm³ cm^-1 a^-1) and maximum displacement depths of 290-445 mm (mean 390 mm). Measured volumetric velocities for these maritime periglacial sites are fairly similar to those recorded in high alpine environments, but markedly less than most reported rates for solifluction in areas of warm permafrost or deep seasonal freezing. Movement affects only the uppermost parts of individual lobes, and the measured volumetric velocities imply either very slow advance of lobe fronts (~ 0.7 mm a^-1) or slow thickening and steepening of stationary lobe risers. Velocity profiles decline approximately exponentially with depth over the depth range 50-400 mm, consistent with movement by frost creep alone or frost creep plus gelifluction. Comparison with measured rates of periglacial mass transport elsewhere on British mountains suggests (1) that, contrary to traditional views, surface velocities are similar to (and may exceed) those of ploughing boulders in the same area, and (2) that both surface velocities and volumetric velocities are markedly less than at unvegetated sites where needle ice creep is the dominant component of solifluction. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/ppp.1761

13036611 Farbrot, Herman (University of Oslo, Department of Geosciences, Oslo, Norway); Isaksen, Ketil; Etzelmuller, Bernd and Gisnas, Kjersti. Ground thermal regime and permafrost distribution under a changing climate in Northern Norway: Permafrost and Periglacial Processes, 24(1), p. 20-38, illus. incl. 3 tables, sketch maps, 45 ref., March 2013.

Since 2002, ground and ground surface temperatures have been systematically measured in the mountains of Troms and Finnmark, northern Norway. These data were used to calibrate and validate a transient heat flow model and a spatial permafrost model, to address ground thermal development since the end of the Little Ice Age, as well as possible permafrost responses to anticipated future climate changes. Approximately 20 per cent of the land area is underlain by permafrost, and in Finnmark, permafrost in palsa mires seems to dominate. Both observations and modelling show that the present permafrost is mainly 'warm', with mean ground temperatures above -3 °C. Permafrost has warmed during the last century, and at one site our ground temperature observations show the degradation of permafrost over the intervening decade. The study identifies three major permafrost regions in northern Norway: (1) maritime mountain permafrost in western Troms; (2) continental permafrost above the treeline and in bogs in Finnmark; and (3) Low Arctic permafrost on the peninsula of Varangerhalvoya, forming a transition between the Scandinavian mountain-dominated permafrost in the south and the arctic permafrost towards the north and east. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/ppp.1763

13036610 Gisnas, Kjersti (University of Oslo, Department of Geosciences, Oslo, Norway); Etzelmuller, Bernd; Farbrot, Herman; Schuler, T. V. and Westermann, S. CryoGRID 1.0; permafrost distribution in Norway estimated by a spatial numerical model: Permafrost and Periglacial Processes, 24(1), p. 2-19, illus. incl. 1 table, sketch maps, 79 ref., March 2013. Includes 3 appendices.

CryoGRID 1.0 provides an equilibrium model of permafrost distribution in Norway at a spatial resolution of 1 km². The approach was forced with gridded data on daily air temperature and snow cover. Ground thermal properties for different bedrock types and sediment covers were derived from surveys and geological maps to yield distributions of thermal conductivity, heat capacity and water content. The distribution of blockfields was derived from satellite images adapting a newly developed classification scheme. The model was evaluated using measured ground surface and ground temperatures, yielding a realistic description of the permafrost distribution in mainland Norway. The model results show that permafrost underlies sites mainly with exposed bedrock or covered by coarse-grained sediments, such as blockfields and coarse tills. In northern Norway, palsa mires are abundant and organic material and vegetation strongly influence the ground thermal regime. Modelling suggests that permafrost in equilibrium with the 1981-2010 climate presently underlies between 6.1 per cent and 6.4 per cent of the total area of mainland Norway, an area significantly smaller than that modelled for the Little Ice Age climate (14%). CryoGRID 1.0 was subsequently forced using output from a regional climate model for the 2071-2100 period, which suggests that severe permafrost degradation will occur, leaving permafrost beneath an area of just 0.2 per cent of mainland Norway. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/ppp.1765

13036615 Sjoberg, Ylva (Stockholm University, Department of Physical Geography, Stockholm, Sweden); Hugelius, Gustaf and Kuhry, Peter. Thermokarst lake morphometry and erosion features in two peat plateau areas of northeast European Russia: Permafrost and Periglacial Processes, 24(1), p. 75-81, illus. incl. 2 tables, sketch maps, 34 ref., March 2013.

High-resolution satellite remote sensing analysis (n = 637 lakes) and field measurements (n = 29 lakes) of two peat plateau areas in northeast European Russia were carried out to investigate lake morphology, map shoreline erosion indicators and assess possible orientation patterns in lake and shore morphology. The study includes the first detailed characterisation of the shape and size of thermokarst lakes in organic terrain. The area covered by lakes is 7.0 per cent and 13.6 per cent, and median lake size is 184 m² and 265 m², respectively, for the two study areas. In both areas, most lakes have a similar northwest to southeast orientation, and shores most commonly face northeast or southwest. The shores are generally steeper and have more cracks and lake depths are greater along shores facing northeast or southeast, and along the shorelines of larger lakes. Shores with a peat substrate are more heterogeneous than those with a mineral substrate in terms of steepness, cracks and water depths. Since the lakes are generally small, the shoreline/area ratio is high and a large part of the peat plateau areas can potentially be affected by shoreline erosion. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/ppp.1762

13036612 Watanabe, Tatsuya (University of Tsukuba, Graduate School of Life and Environmental Sciences, Ibaraki, Japan); Matsuoka, Norikazu and Christiansen, Hanne H. Ice- and soil-wedge dynamics in the Kapp Linne area, Svalbard, investigated by two- and three-dimensional GPR and ground thermal and acceleration regimes: Permafrost and Periglacial Processes, 24(1), p. 39-55, illus. incl. 3 tables, sketch map, 50 ref., March 2013.

GPR is applied to image subsurface structures below non-sorted polygons in Kapp Linne, Svalbard, where ice and active-layer soil wedges co-exist within a small area. Two-dimensional GPR images ice wedges as hyperbolic reflections extending down from the frost table. However, some ice-wedge signals are obscured or masked by similar hyperbolic reflections produced by stones or active-layer soil wedges. Three-dimensional GPR images ice wedges as linear amplitude anomalies, which excludes the possibility of misinterpretation and offers more reliable results. GPR investigations show that ice wedges are distributed sporadically in lower (younger) beach ridges, but not in higher (older) ones. Inter-site monitoring of ground temperature, soil moisture, slow ground deformation and cracking during 2004-09 and the determination of near-surface soil texture and stratigraphy suggest that snow cover and soil thermal properties determine the distribution of ice wedges. Most ice wedges are considered to be inactive due to relatively high permafrost temperatures. Shock loggers and extensometers detected shallow (soil wedge) cracking in sandy sediments, when the ground surface temperature dropped to -12°C and the thermal gradient in the upper 20 cm of ground reached -10°C m^-1. Abstract Copyright (2010), John Wiley & Sons, Ltd.

DOI: 10.1002/ppp.1767

13039820 Zhang Ruibin (Nanjing Agricultural University, College of Resources and Environmental Sciences, Nanjing, China); He Jun; Zhao Yanwen; Peng Yao and Fu Li. Another important factor of rising sea level; soil erosion: Clean (Weinheim), 41(2), p. 174-178, illus., 51 ref., February 2013.

Global mean sea level is a sensitive factor of climate change. Global warming will contribute to worldwide sea-level rise from thermal expansion of ocean water, melting of glaciers and polar ice. Consideration of global soil erosion, water vapor cycle, and hydraulic actions suggests that soil erosion is another important factor contributing to sea-level rise in addition to global warming. Much terrestrial sediment flows into the rivers each year but cannot be replenished, resulting in land surface declines. Moreover, sediment flow into rivers and oceans contributes to rising sea level. Ecological protection measure was proposed to prevent rising sea levels caused by soil erosion. This commentary should be useful to attract attention on rising sea levels caused by soil erosion. Abstract Copyright (2013), WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI: 10.1002/clen.201200127

13036209 Motuzova, G. V. (Lomonosov Moscow State University, Moscow, Russian Federation); Makarychev, I. P. and Petrov, M. I. Effect of aluminum, zinc, copper, and lead on the acid-base properties of water extracts from soils: Eurasian Soil Science, 46(1), p. 44-50, illus., 29 ref., January 2013. Based on Publisher-supplied data.

The potentiometric titration of water extracts from the upper horizons of taiga-zone soils by salt solutions of heavy metals (Pb, Cu, and Zn) showed that their addition is an additional source of the extract acidity because of the involvement of the metal ions in complexation with water-soluble organic substances (WSOSs). At the addition of 0.01 M water solutions of Al(NO₃)₃ to water extracts from soils, Al³⁺ ions are also involved in complexes with WSOSs, which is accompanied by stronger acidification of the extracts from the upper horizon of soddy soils (with a near-neutral reaction) than from the litter of bog-podzolic soil (with a strongly acid reaction). The effect of the Al³⁺ hydrolysis on the acidity of the extracts is insignificantly low in both cases. A quantitative relationship was revealed between the release of protons and the ratio of free Cu²⁺ ions to those complexed with WSOSs at the titration of water extracts from soils by a solution of copper salt. Copyright 2013 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229313010067

13041151 Zhang Dan (Yunnan Agricultural University, College of Resources and Environment, Kunming, China); Chen Anqiang; Xiong Donghong and Liu Gangcai. Effect of moisture and temperature conditions on the decay rate of a purple mudstone in southwestern China: Geomorphology, 182, p. 125-132, illus. incl. 4 tables, sketch map, 75 ref., January 15, 2013.

Soil formation and geomorphology are primarily influenced by the rock decay, which in turn is strongly determined by moisture and temperature conditions. However, it remains unclear whether rock decay is dominated by thermal stresses or by hydration disintegration, and there is little information on mudstone decay rate in southwestern China. This study hypothesized that rock decay is dominated by hydration mechanism, and focused on the physical decay characteristics of typical purple mudstones using a combination of field and laboratory-based experiments. The bedrock of a Penglaizhen group (J₃p) in Yanting County, Sichuan Province, southwestern China, was exposed and covered with nylon fabric in situ. Soil depths of 10, 20, 40 and 60 cm were laid on this nylon fabric in 2003, and the decay rate (the quantity of clastic particles <2 mm that were decayed from the bedrock, in t km^-2yr^-1) under the nylon fabric was measured both in 2005 and 2009. In addition, fresh mudstones sampled from the Matoushan group (K₂m), the Tuodian group (J₃t) and the Lufeng group (J₁l) in Yuanmou County, Shuangbai County, and Lufeng County of Yunnan Province, southwestern China, respectively, were subjected to alternating applications of moisture, temperature and their interaction (seven treatments) in the laboratory, and their decay ratios (the mass of decayed rock of <2 mm clastic particles to sampled rock mass, in percent) were measured in 2010. In the field, the decay rate of the bedrock showed a significant (p<0.05) positive relationship with both the daily moisture and temperature variation at the interface between the soil and bedrock. In the laboratory, results showed that the effect of moisture variation, but not temperature alternation, on rock decay was apparent, suggesting that purple rock decay is dominated by hydration mechanism. Freezing-thawing in particular affects the sampled rocks, because it causes more spalling and fracturing. The J₃t rock had the highest decay ratio because it had the highest clay mineral content and porosity of the three rock types. Hierarchical clustering analysis suggested that the variation of moisture content and H₂O phase (solid or liquid) within rock plays a key role in rock decay processes. Both field and laboratory studies consistently showed that the alteration of wetting-drying and freezing-thawing, as well as moisture content, substantially influenced rock decay. Abstract Copyright (2013) Elsevier, B.V.

DOI: 10.1016/j.geomorph.2012.11.003

13038008 Di Nicola, Luigia (Scottish Universities Environmental Research Centre, East Kilbride, United Kingdom); Baroni, Carlo; Strasky, Stefan; Salvatore, Maria Cristina; Schlüchter, Christian; Akcar, Naki; Kubik, Peter W. and Wieler, Rainer. Multiple cosmogenic nuclides document the stability of the East Antarctic ice sheet in northern Victoria Land since the late Miocene (5-7 Ma): Quaternary Science Reviews, 57, p. 85-94, illus. incl. 2 tables, geol. sketch map, 84 ref., December 4, 2012.

The timing and amplitude of changes in the Antarctic ice level are relevant to understanding past climate fluctuations and ongoing changes in the global climate and sea levels. In this study, we present surface exposure ages based on in situ produced cosmogenic ¹⁰Be and ²¹Ne in the bedrock samples of glacially eroded relict surfaces from the Deep Freeze Range, northern Victoria Land. The proximity of this region to the East Antarctic Ice Sheet indicates that the area is sensitive to variations in inland ice volume, permitting the investigation of the behavioural relationship between the East Antarctic Ice Sheet and the alpine glacial system in northern Victoria Land. Dating erosional surfaces provides a precise chronology of northern Victoria Land paleoclimate evolution and allows us to correlate the East Antarctic Ice Sheet response to global climate events and local ice level variations. The ¹⁰Be and ²¹Ne concentrations from the highest peaks of the Deep Freeze Range strongly indicate that the relict landscape features were continuously exposed for 5-7 Ma. Denudation rates inferred from our data show that the erosion rate of the summits has been extremely low (~5 cm/Ma) for at least 5-7 Ma. Along with evidence of persistent climate stability (cold and arid conditions) from other sectors of the Transantarctic Mountains, our results indicate that the transition from the wet-based to the cold-based glacial regime in northern Victoria Land occurred after the creation of the polar East Antarctic Ice Sheet in the Middle Miocene. Abstract Copyright (2012) Elsevier, B.V.

DOI: 10.1016/j.quascirev.2012.09.026

13040971 Ficklin, Darren L. (Santa Clara University, Department of Environmental Studies and Sciences, Santa Clara, CA); Stewart, Iris T. and Maurer, Edwin P. Projections of 21st century Sierra Nevada local hydrologic flow components using an ensemble of general circulation models: Journal of the American Water Resources Association, 48(6), p. 1104-1125, illus. incl. 5 tables, 102 ref., December 2012.

Sierra Nevada snowmelt and runoff is a key source of water for many of California's 38 million residents and nearly the entire population of western Nevada. The purpose of this study was to assess the impacts of expected 21st Century climatic changes in the Sierra Nevada at the subwatershed scale, for all hydrologic flow components, and for a suite of 16 General Circulation Models (GCMs) with two emission scenarios. The Soil and Water Assessment Tool (SWAT) was calibrated and validated at 35 unimpaired streamflow sites. Results show that temperatures are projected to increase throughout the Sierra Nevada, whereas precipitation projections vary between GCMs. These climatic changes drive a decrease in average annual streamflow and an advance of snowmelt and runoff by several weeks. The largest streamflow reductions were found in the mid-range elevations due to less snow accumulation, whereas the higher elevation watersheds were more resilient due to colder temperatures. Simulation results showed that decreases in snowmelt affects not only streamflow, but evapotranspiration, surface, and subsurface flows, such that less water is available in spring and summer, thus potentially affecting aquatic and terrestrial ecosystems. Declining spring and summer flows did not equally affect all subwatersheds in the region, and the subwatershed perspective allowed for identification for the most sensitive basins throughout the Sierra Nevada. Abstract Copyright (2012), American Water Resources Association.

DOI: 10.1111/j.1752-1688.2012.00675.x

13038137 Schmidt, S. (James Hutton Institute, Invergowrie, United Kingdom); Bengough, A. G.; Gregory, P. J.; Grinev, D. V. and Otten, W. Estimating root-soil contact from 3D X-ray microtomographs: European Journal of Soil Science, 63(6), p. 776-786, illus. incl. 4 tables, 33 ref., December 2012.

Adequate contact with the soil is essential for water and nutrient adsorption by plant roots, but the determination of root-soil contact is a challenging task because it is difficult to visualize roots in situ and quantify their interactions with the soil at the scale of micrometres. A method to determine root-soil contact using X-ray microtomography was developed. Contact areas were determined from 3D volumetric images using segmentation and iso-surface determination tools. The accuracy of the method was tested with physical model systems of contact between two objects (phantoms). Volumes, surface areas and contact areas calculated from the measured phantoms were compared with those estimated from image analysis. The volume was accurate to within 0.3%, the surface area to within 2-4%, and the contact area to within 2.5%. Maize and lupin roots were grown in soil (<2 mm) and vermiculite at matric potentials of -0.03 and -1.6 MPa and in aggregate fractions of 4-2, 2-1, 1-0.5 and < 0.5 mm at a matric potential of -0.03 MPa. The contact of the roots with their growth medium was determined from 3D volumetric images. Macroporosity (>70 mm) of the soil sieved to different aggregate fractions was calculated from binarized data. Root-soil contact was greater in soil than in vermiculite and increased with decreasing aggregate or particle size. The differences in root-soil contact could not be explained solely by the decrease in porosity with decreasing aggregate size but may also result from changes in particle and aggregate packing around the root. Abstract Copyright (2012), British Society of Soil Science.

DOI: 10.1111/j.1365-2389.2012.01487.x

13038139 Simola, Heikki (University of Eastern Finland, Department of Biology, Joensuu, Finland); Pitkanen, A. and Turunen, J. Carbon loss in drained forestry peatlands in Finland, estimated by re-sampling peatlands surveyed in the 1980s: European Journal of Soil Science, 63(6), p. 798-807, illus. incl. 1 table, sketch map, 38 ref., December 2012.

The total area of boreal peatlands is about 3.5 million km² and they are estimated to contain 15-30% of the global soil carbon (C) storage. In Finland, about 60 000 km², or 60% of the original peatland area, has been drained, mainly for forestry improvement. We have studied C inventory changes on forestry-drained peatlands by re-sampling the peat stratum in 2009 at the precise locations of quantitative peat mass analyses conducted as part of peatland transect surveys during the 1980s. The old and new profiles were correlated mainly by their ignition residue stratigraphies; at each site we determined a reference level, identifiable in both profiles, and calculated the cumulative dry mass and C inventories above it. Comparison of a total of 37 locations revealed broad variation, from slight increase to marked decrease; on average the 2009 results indicate a loss of 7.4 (SE ± 2.5) kg m^-2 dry peat mass when compared with the 1980s values. Expressed on an annual basis, the results indicate an average net loss of 150 g C m^-2 year^-1 from the soil of drained forestry peatlands in the central parts of Finland. The C balance appeared not to correlate with site fertility (fertility classes according to original vegetation type), nor with post-drainage timber growth. Abstract Copyright (2012), British Society of Soil Science.

DOI: 10.1111/j.1365-2389.2012.01499.x

13038004 Zimov, S. A. (Russian Academy of Sciences, Pacific Institute for Geography, Cherskii, Russian Federation); Zimov, N. S.; Tikhonov, A. N. and Chapin, F. S., III. Mammoth steppe; a high-productivity phenomenon: Quaternary Science Reviews, 57, p. 26-45, illus., 54 ref., December 4, 2012.

At the last deglaciation Earth's largest biome, mammoth-steppe, vanished. Without knowledge of the productivity of this ecosystem, the evolution of man and the glacial-interglacial dynamics of carbon storage in Earth's main carbon reservoirs cannot be fully understood. Analyzes of fossils ¹⁴C dates and reconstruction of mammoth steppe climatic envelope indicated that changing climate wasn't a reason for extinction of this ecosystem. We calculate, based on animal skeleton density in frozen soils of northern Siberia, that mammoth-steppe animal biomass and plant productivity, even in these coldest and driest of the planet's grasslands were close to those of an African savanna. Numerous herbivores maintained ecosystem productivity. By reducing soil moisture and permafrost temperature, accumulating carbon in soils, and increasing the regional albedo, mammoth-steppe amplified glacial-interglacial climate variations. The re-establishment of grassland ecosystems would slow permafrost thawing and reduce the current warming rate. Proposed methods can be used to estimate animal density in other ecosystems. Abstract Copyright (2012) Elsevier, B.V.

DOI: 10.1016/j.quascirev.2012.10.005

13040898 Soina, V. S. (Lomonosov Moscow State University, Faculty of Soil Science, Moscow, Russian Federation); Lysak, L. V.; Konova, I. A.; Lapygina, E. V. and Zvyagintsev, D. G. Study of ultramicrobacteria (nanoforms) in soils and subsoil deposits by electron microscopy: Eurasian Soil Science, 45(11), p. 1048-1056, 35 ref., November 2012. Based on Publisher-supplied data.

The use of multiple centrifuging and filtration of water suspensions from different soils and subsoil deposits allowed revealing the ultrafine forms (nanosized, nanoforms) of bacteria. In the soils studied, the number of bacteria obtained by filtration using 0.2-mm filters was 20-300 mln cells in 1 g soil; the share of these bacteria of their total population in the natural soils reached 5% and was higher (up to 15%) in the polluted urban soils. The study of bacterial nanoforms in situ by the methods of scanning and transmission microscopy has shown the presence of dividing cells, which testifies to their viability. The cells without signs of division were similar in their ultrastructural characteristics to dormant forms of nonspore-forming bacteria. They were observed in permafrost deposits. The data obtained attest that the bacterial nanoforms are widespread in soils and subsoil deposits. According to their morphological and cytological characteristics, they are represented by both active and dormant forms to survive unfavorable conditions. Copyright 2012 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229312110087

13040925 Atroshchenko, F. G. (Research Institute of Geomechanics and Surveying (VNIMI), Saint Petersburg, Russian Federation). Otsenka gidrogeologicheskikh usloviy podzemnoy razrabotki mestorozhdeniya trubki "Udachnaya" [Assessment of hydrogeological conditions of underground exploitation of the Udachnaya diamondiferous pipe]: Geoekologiya (Moskva), 2012(5), p. 414-421 (English sum.), illus. incl. 3 tables, 8 ref., October 2012.

In the Yakut diamond province, the open-pit industrial development of diamond pipes has been almost finished. In this regard, the majority of mining and processing works at the ALROSA Joint-Stock Co. are regularly passing to the underground mining. Measures on the elimination of possible underground water in-rush are very important, as they can cause flooding of mine workings. The estimation of forecast inflows is given with the reference to the adopted mining method with roof caving and drainage water discharge to the subsurface permafrost.

13040880 Long, Michael (University College, Dublin, Ireland); Daynes, Philip; Donohue, Shane and Looby, Michael. Retaining wall behaviour in Dublin's fluvio-glacial gravel, Ireland: Proceedings of the Institution of Civil Engineers. Geotechnical Engineering, 165(5), p. 289-307, illus. incl. 3 tables, geol. sketch maps, 30 ref., October 2012.

Practising engineers in the Dublin, Ireland, area have significant experience in dealing with the Boulder Clay which underlies much of the city. However, the 45 m deep buried pre-glacial channel north of the River Liffey is infilled with fluvio-glacial deposits which behave very differently from an engineering point of view. Case history data from eight sites and a detailed examination of the retaining wall behaviour at two of the sites show that retaining wall movements appear to be governed by system stiffness (i.e. a combination of wall stiffness and support configuration). It seems that relatively simple beam-spring type computer programs will provide data for reasonably accurate designs of retaining walls for basements of up to two levels. Input parameters such as K_o, f' and soil stiffness need to be carefully specified. Groundwater inflows can be significant but can be dealt with by providing a good cut-off into the underlying glacial till or bedrock and by conventional pumping techniques. Geophysical techniques such as multichannel analysis of surface waves, S/P waves and resistivity can be very useful for the determination of soil properties, such as degree of saturation, density and stiffness, and for material characterisation (i.e. distinguishing the presence of these materials in contrast to the Boulder Clay).

URL: http://dx.doi.org/10.1680/geng.9.00099

13039674 Mergelov, N. S. (Russian Academy of Sciences, Institute of Geography, Moscow, Russian Federation); Goryachkin, S. V.; Shorkunov, I. G.; Zazovskaya, E. P. and Cherkinsky, A. E. Endolithic pedogenesis and rock varnish on massive crystalline rocks in East Antarctica: Eurasian Soil Science, 45(10), p. 901-917, illus., 52 ref., October 2012. Based on Publisher-supplied data.

Desert varnish and endolithic organisms are two widespread phenomena that have been studied in detail separately; their interaction and their genetic relationships have virtually escaped the attention of researchers. Both phenomena are of indubitable interest for pedology: endolithic organisms as an agent of soil formation and rock varnish as a probable product of pedogenesis. It is argued that the system of endolithic organisms, their functioning products, and the rock has all the features inherent to soils: the rock layer subjected to the influence of external abiogenic factors and living organisms dwelling in the rock and synthesizing and decomposing organic substances. The action of biogenic and abiogenic agents leads to the in situ transformation of the rock with the accumulation and removal of the products of this transformation and with the development of vertical heterogeneity in the form of microhorizons composing the soil microprofile. Instrumental measurements indicate that the carbon content in the endolithic horizons developed by biota in granitoid rocks of the Larsemann Hills oasis varies from 0.2 to 3.3%, the nitrogen content in these horizons varies from 0.02 to 0.47%, and the radiocarbon age of their organic matter reaches 480 ± 25 yrs. The products of the pedogenesis are represented by fine earth materials and by abundant and often multilayered films and coatings on the rock surface and on the lower sides of the desquamation (spalling) plates. Scanning electron microscopy with X-ray microprobe analysis indicates that the major elements composing these films are O, C, Si, Al, Fe, Ca, Mg, and S. It is shown that the films of the rock varnish and the organomineral films in the fissured zone of the rock under the plate with endolithic communities have certain similarity in their morphology and composition: the films of the rock varnish also contain biota (dead cells or cells in the dormant state), and their botryoidal structure is similar to the structure of the biofilms inside the endolithic system. In both types of films, amorphous aluminum and silicon compounds are present, and the accumulation of Fe, Ca, Mg, S, Cl, and some other elements takes place. It is argued that some varieties of rock varnish are the products of endolithic pedogenesis; in essence, they represent the horizons of micropaleosols exposed to the surface in the course of spalling and then transformed by the external environmental agents. Copyright 2012 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229312100067

13037167 Berdnikov, N. M. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Kriosfery Zemli, Tyumen, Russian Federation). Bugry pucheniya v razlichnykh landshaftakh basseyna reki Nadym [Frost mounds in different landscapes of the Nadym River basin]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 81-86 (English sum.), illus., 18 ref., September 2012.

The morphology of frost mounds and their cryogenic structure have been studied in northern taiga of West Siberia by means of drilling of boreholes to the depth of 10 m and surface levelings. Significant distinctions in morphological and cryolithological features of mounds in different landscapes have been revealed. Distinctions have been established. A diameter to height relation has been calculated for frost mounds. The influence of moistening degree and structure of natural-territorial complex on the moisture of frozen ground and mounds convexity has been demonstrated. Features of occurrence of contemporary cryogenic heave processes and their geomorphological effect have been examined.

13037161 Fotiyev, S. M. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Kriosfery Zemli, Tyumen, Russian Federation). Khimicheskiy sostav i genezis vody, sformirovavshey povtorno-in"yektsionnyye plastovyye l'dy na ploshchadi Bovanenkovskogo mestorozhdeniya [Chemical composition and genesis of water that formed the repeatedly injected massive ice beds in the Bovanenkovo Field area]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 3-28 (English sum.), illus. incl. 7 tables, 35 ref., September 2012.

The conditions of forming the cryohydrochemical structure of the deposits of marine plains, including the repeatedly injected massive ice beds, the ion-saline composition and the mineralization of the massive ice bed in the layers of one stratum, the dependence of the ion-saline composition of the massive ice beds on the degree of their mineralization, the chemical composition and the share of various kinds of natural waters in the formation of massive ice beds, and the reasons of change of their initial chemical composition have been examined sequentially. It has been demonstrated that in the severe climatic and geocryological conditions of Yamal the lakes were the exclusive sources which could provide the regular entry of the enormous volumes of ultra-fresh water into the stratum of frozen marine deposits. The hydrochemical similarities of the chemical composition and the mineralization of the repeatedly injected massive ice beds and lake water have been proved.

13037163 Galanin, A. A. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Merzlotovedeniya, Yakutsk, Russian Federation). Vozrast poslednego lednikovogo maksimuma na severo-vostoke Azii [Age of the last glacial maximum in northeastern Asia]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 39-52 (English sum.), illus. incl. sketch map, 39 ref., September 2012.

The analysis of geomorphic and biostratigraphic data on four key Late Glacial complexes located in the mountains of Cherskiy Range and Kolyma Upland has demonstrated that the Late Glaciation had reached its maximum in the second part of Karginskiy Thermochron (MIS 3) and it had formed in the conditions of a moderate humid and cool (subarctic) climate. The Glaciation was considerably reduced at the end of Karginskiy Termochrone (MIS 3). During Sartan Cryochron (MIS 2) the degradation of the Glaciation had continued and the Periglacial Area was widespread and accompanied with eolian and permafrost processes. At the boundary of the Pleistocene and Holocene small cirque-type glaciation had occurred due to the marine transgression. The last Holocene glacial activity is related to Neoglacial Epoch and it appeared with the rock glaciers formation development.

13037168 Korobova, T. A. (Rossiyskaya Akademiya Nauk, Sibirskoye Otdeleniye, Institut Kriosfery Zemli, Tyumen, Russian Federation). Kartografo-matematicheskiy analiz neodnorodnosti morfologicheskoy struktury landshaftov i geokriologicheskikh usloviy Zapadnogo Yamala [Cartographic-mathematical analysis of heterogeneity of landscape morphological structure and permafrost conditions of western Yamal]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 87-93 (English sum.), illus. incl. sketch map, 17 ref., September 2012.

A cartographic-mathematical analysis of heterogeneity of the landscape morphological structure of typical Western Yamal tundras has been fulfilled on the basis of the calculation of the landscape heterogeneity coefficient. A map of zoning of the investigated area versus the heterogeneity of landscape and permafrost conditions has been created. The author considers the importance of cartographic-mathematical analysis of heterogeneity of landscape morphological structure for selection of the basic principles of linear plotting facilities and construction. By the example of the potential pipeline routes, the optimal way of their installation has been offered.

13037164 Maksimova, L. N. (Moskovskiy Gosudarstvennyy Universitet, Moscow, Russian Federation) and Ospennikov, E. N. Evolyutsiya bolotnykh sistem i merzlotnykh usloviy Bol'shezemel'skoy undry v golotsene [Evolution of mire systems and permafrost of Bolshezemelskaya Tundra in the Holocene]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 53-61 (English sum.), illus., 25 ref., September 2012.

This research is based on a complex approach to the study of the mire system evolution. The joint analysis of the dynamics of the mire systems and permafrost conditions of Bolshezemelskaya tundra in the Holocene has been carried out. New C-14-datings of peat of interfluve areas have been given. It has been demonstrated that the evolution of mire systems were determined by the interaction of the mire-forming and cryogenic processes.

13037165 Osadchaya, G. G. (Institut Upravleniya, Informatsii i Biznesa, Ukhta, Russian Federation) and Tumel', N. V. Lokal'nyye landshafty kak undikatory geokriologicheskoy zonal'nosti (na primere Yevropeyskogo severo-vostoka) [Local landscapes as indicators of geocryological zoning (example from northeastern Europe)]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 62-71 (English sum.), illus. incl. table, sketch map, 26 ref., September 2012.

Geocryological zoning is demonstrated in regular changes of the character of permafrost parameters of a territory. There are considerable discords when defining geocryological zoning of Bolshezemelskaya tundra, which demands defining more precisely the borders of geocryological zoning and subzones. It is supposed to use the landscapes-indicators (in range of local landscapes) as the main index of zone inclusion. It is possible to use the groups of forest, marshy, tundra local landscapes and peatbogs as indicators. On the whole the cryogenic relief is the most considerable index when the local landscapes-indicators are used for geocryological zoning. That is why the universal group of indicators is the group of peatbogs, seldom tundra. Marshy local landscapes are practically not used for an indication. Forest local landscapes in some cases can be the indicators, but they do not depend on frost characteristics.

13037166 Romanenko, F. A. (Moskovskiy Gosudarstvennyy Universitet, Moscow, Russian Federation) and Garankina, E. V. Formirovaniye i stroyeniye mnogoletnemeerzlykh porod u yuzhnoy granitsy kriolitozony na Kol'skom poluostrove [Permafrost formation and structure at the southern border of the cryolithozone, Kola Peninsula]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 72-80 (English sum.), illus. incl. sketch map, 22 ref., September 2012.

Results of fieldworks in the northwestern (areas of Nikel), central (low mountains of Khibiny, Lovozerskiye tundras and adjacent plains) and northwestern (basin of Kachkovka River) parts of the Kola Peninsula have been examined. The lithologic content, the age, the cryogenic textures, the isotopic composition of frozen ground and the thermokarst relief have been analyzed. The permafrost has been dated. It has been demonstrated that the modern permafrost distribution at the Kola Peninsula has practically not changed since the middle of the XX century despite the significant climate warming.

13037162 Vasil'chuk, Yu. K. (Moskovskiy Gosudarstvennyy Universitet, Moscow, Russian Federation). Rubezh pleystotsena i golotsena; okolo 10 tysyach let nazad; vremya korennoy smeny tipichnykh geokriologicheskikh obrazovaniy [The Pleistocene-Holocene transition at 10 ka BP as the time of radical changes of typical geocryological formations]: Kriosfera Zemli = Earth Cryosphere, 16(3), p. 29-38 (English sum.), illus. incl. 5 tables, 55 ref., September 2012.

The geocryologic situation changed radically at the Pleistocene-Holocene turn about 10 ka BP. This led to the replacement of typical geocryologic formations. Accumulation of the late Pleistocene syncryogenic formation "edoma" was completed, and intense accumulation of Holocene syncryogenic formation began in the vast areas of North Eurasia and North America. Cryolithologic indicators have been the most reliable criteria for the Pleistocene-Holocene differentiation in permafrost. Edoma sediments with large syngenetic ice wedges and massive ice in salty ground have been the cryolithologic indicators specific exclusively for the late Pleistocene. Cryolithologic indicators of the Holocene are Holocene ice wedges, palsas and pingos. They have not been found in the Pleistocene.

13039569 Berger, Tobias (Linnaeus University, School of Natural Sciences, Kalmar, Sweden); Peltola, P.; Drake, H. and Astrom, M. Impact of a fluorine-rich granite intrusion on levels and distribution of fluoride in a small boreal catchment: Aquatic Geochemistry, 18(2), p. 77-94, illus. incl. 2 tables, sketch map, 45 ref., March 2012.

This paper explores the influence of a fluorine-rich granite on fluoride concentration in a small boreal catchment in northern Europe. The materials include stream water and shallow groundwater sampled in spatial and temporal dimensions, and analytical data on fluoride and a number of ancillary variables. Fluoride increased strongly towards the lower reaches of the catchment-at the stream outlet the concentrations were up to 4.2 mg L^-1 and 1.6-4.7 times higher than upstream. Additionally, fluoride concentrations were particularly high in groundwater and small surface-water bodies (including quarries) above or in direct contact with the granite and showed a strong inverse correlation with water discharge in the stream. Taken together, these data and patterns pin-point the granite intrusion as the ultimate source, explaining the abundance and distribution of dissolved fluoride within the catchment. The granite most likely deliver fluoride to the stream by three mechanisms: (1) weathering of the fine fraction of glacial deposits, derived from the granite and associated fluorine-rich greisen alterations, (2) large relative input of baseflow, partially originating in the granite and greisen, into the lower reaches during low flow in particular, and (3) water-conducting fractures or fracture zones running through the fluorine-rich granite and greisen. Copyright 2012 Springer Science+Business Media B.V.

DOI: 10.1007/s10498-011-9151-2

13037526 Lupachev, A. V. (Russian Academy of Sciences, Institute of Physicochemical and Biological Problems in Soil Sciences, Pushchino, Russian Federation) and Gubin, S. V. Suprapermafrost organic-accumulative horizons in the tundra Cryozems of northern Yakutia: Eurasian Soil Science, 45(1), p. 45-55, illus., 28 ref., January 2012. Based on Publisher-supplied data; original Russian text; Lupachev, A. V., and Gubin S. V., 2012, published in Pochvovedenie, Vol. 2012, No. 1, pp. 57-68.

Organic-accumulative horizons above the permafrost table have been described in the profiles of cryozems developing on interfluve surfaces in the tundra zone of northern Yakutia. The organic matter content in these suprapermafrost horizons is comparable with or even exceeds the organic matter content in the surface horizons. The dynamics of seasonal thawing specify the annual involvement of the material of these horizons into the zone of active pedogenesis or its exclusion from it in the case of their frozen state. The analysis of the morphology of cryozems of the Kolyma Lowland along a 1000-km-long sublatitudinal transect shows that the accumulation and migration of raw organic materials (predominantly, differently decomposed peat) above the permafrost table take place upon the particular combinations of local factors (the soil moistening, ice content, freezing-thawing conditions, nanotopography of the permafrost table, etc.) at the lower boundary of the active layer. The well-pronounced accumulation of the raw organic material in the suprapermafrost horizons can be reflected in the substantive characteristics of these horizons and should be taken into account in classification decisions. Copyright 2012 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229312010115

13037853 Putys, P. (Lithuanian Geological Survey, Vilnius, Lithuania) and Giedraitiene, J. Pozeminio vandens aktyviosios apytakos zonos hidrogeotermija--Geothermal regime of active groundwater exchange zone: in Lietuvos Geologijos Tarnybos; 2011 metu veiklos rezultati--Lithuanian Geological Survey; annual report 2011 (Satkunas, J., editor; et al.), Lietuvos Geologijos Tarnybos ... Metu Veiklos Rezultatai = Geological Survey of Lithuania Annual Report, 2011, p. 38-44, (Lithuanian, English), illus. incl. sketch maps, 2012.

13042832 Riechelmann, S. (Ruhr-University Bochum, Institute for Geology, Mineralogy and Geophysics, Bochum, Germany); Buhl, D.; Schröder-Ritzrau, A.; Riechelmann, D. F. C.; Richter, D. K.; Vonhof, H. B.; Wassenburg, J. A.; Geske, A.; Spötl, C. and Immenhauser, A. The magnesium isotope record of cave carbonate archives: Climate of the Past, 8(6), p. 1849-1867, illus. incl. 4 tables, sketch maps, 92 ref., 2012. Part of special issue no. 47, Advances in understanding and applying speleothem climate proxies, edited by Mangini, A., URL: http://www.clim-past.net/special_issue47.html; published in Climate of the Past Discussion: 22 May 2012, URL: http://www.clim-past-discuss.net/8/1835/2012/cpd-8-1835-2012.html; accessed in Jan., 2013.

Here we explore the potential of magnesium (d²⁶Mg) isotope time-series data as continental climate proxies in speleothem calcite archives. For this purpose, a total of six Pleistocene and Holocene stalagmites from caves in Germany, Morocco and Peru and two flowstones from a cave in Austria were investigated. These caves represent the semi-arid to arid (Morocco), the warm-temperate (Germany), the equatorial-humid (Peru) and the cold-humid (Austria) climate zones. Changes in the calcite magnesium isotope signature with time are compared against carbon and oxygen isotope records from these speleothems. Similar to other proxies, the non-trivial interaction of a number of environmental, equilibrium and disequilibrium processes governs the d²⁶Mg fractionation in continental settings. These include the different sources of magnesium isotopes such as rainwater or snow as well as soil and host rock, soil zone biogenic activity, shifts in silicate versus carbonate weathering ratios and residence time of water in the soil and karst zone. Pleistocene stalagmites from Morocco show the lowest mean d²⁶Mg values (GDA: -4.26±0.07 per mil and HK3: -4.17±0.15 per mil), and the data are well explained in terms of changes in aridity over time. The Pleistocene to Holocene stalagmites from Peru show the highest mean value of all stalagmites (NC-A and NC-B d²⁶Mg: -3.96±0.04 per mil) but only minor variations in Mg-isotope composition, which is consistent with the rather stable equatorial climate at this site. Holocene stalagmites from Germany (AH-1 mean d²⁶Mg: -4.01±0.07 per mil; BU 4 mean d²⁶Mg: -4.20±0.10 per mil) suggest changes in outside air temperature was the principal driver rather than rainfall amount. The alpine Pleistocene flowstones from Austria (SPA 52: -3.00±0.73 per mil; SPA 59: -3.70±0.43 per mil) are affected by glacial versus interglacial climate change with outside air temperature affecting soil zone activity and weathering balance. Several d²⁶Mg values of the Austrian and two d²⁶Mg values of the German speleothems are shifted to higher values due to sampling in detrital layers (Mg-bearing clay minerals) of the speleothems. The data and their interpretation shown here highlight the potential but also the limitations of the magnesium isotope proxy applied in continental climate research. An obvious potential lies in its sensitivity for even subtle changes in soil-zone parameters, a hitherto rather poorly understood but extremely important component in cave archive research. Limitations are most obvious in the low resolution and high sample amount needed for analysis. Future research should focus on experimental and conceptual aspects including quantitative and well-calibrated leaching and precipitation experiments.

URL: http://www.clim-past.net/8/1849/2012/cp-8-1849-2012.pdf

13042835 Schwamborn, Georg (Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany); Fedorov, G.; Ostanin, N.; Schirrmeister, L. and Andreev, Andrei. Depositional dynamics in the El'gygytgyn Crater margin; implications for the 3.6 Ma old sediment archive: Climate of the Past, 8(6), p. 1897-1911, illus. incl. strat. cols., sketch maps, 52 ref., 2012. Part of special issue no. 48, Initial results from lake El'gygytgyn, western Beringia; first time-continuous Pliocene-Pleistocene terrestrial record from the Arctic, edited by Brigham-Grette, J., et al., URL: http://www.clim-past.net/special_issue48.html; published in Climate of the Past Discussion: 14 June 2012, URL: http://www.clim-past-discuss.net/8/2187/2012/cpd-8-2187-2012.html; accessed in Jan., 2013.

The combination of permafrost history and dynamics, lake level changes and the tectonical framework is considered to play a crucial role for sediment delivery to El'gygytgyn Crater Lake, NE Russian Arctic. The purpose of this study is to propose a depositional framework based on analyses of the core strata from the lake margin and historical reconstructions from various studies at the site. A sedimentological program has been conducted using frozen core samples from the 141.5 m long El'gygytgyn 5011-3 permafrost well. The drill site is located in sedimentary permafrost west of the lake that partly fills the El'gygytgyn Crater. The total core sequence is interpreted as strata building up a progradational alluvial fan delta. Four macroscopically distinct sedimentary units are identified. Unit 1 (141.5-117.0 m) is comprised of ice-cemented, matrix-supported sandy gravel and intercalated sandy layers. Sandy layers represent sediments which rained out as particles in the deeper part of the water column under highly energetic conditions. Unit 2 (117.0-24.25 m) is dominated by ice-cemented, matrix-supported sandy gravel with individual gravel layers. Most of the Unit 2 diamicton is understood to result from alluvial wash and subsequent gravitational sliding of coarse-grained (sandy gravel) material on the basin slope. Unit 3 (24.25-8.5 m) has ice-cemented, matrix-supported sandy gravel that is interrupted by sand beds. These sandy beds are associated with flooding events and represent near-shore sandy shoals. Unit 4 (8.5-0.0 m) is ice-cemented, matrix-supported sandy gravel with varying ice content, mostly higher than below. It consists of slope material and creek fill deposits. The uppermost metre is the active layer (i.e. the top layer of soil with seasonal freeze and thaw) into which modern soil organic matter has been incorporated. The nature of the progradational sediment transport taking place from the western and northern crater margins may be related to the complementary occurrence of frequent turbiditic layers in the central lake basin, as is known from the lake sediment record. Slope processes such as gravitational sliding and sheet flooding occur especially during spring melt and promote mass wasting into the basin. Tectonics are inferred to have initiated the fan accumulation in the first place and possibly the off-centre displacement of the crater lake.

URL: http://www.clim-past.net/8/1897/2012/cp-8-1897-2012.pdf

13043975 Swingedouw, Didier (Institute Pierre Simon Laplace, Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France); Terray, L.; Servonnat, Jerome and Guiot, Joel. Mechanisms for European summer temperature response to solar forcing over the last millennium: Climate of the Past, 8(5), p. 1487-1495, illus. incl. sketch maps, 33 ref., 2012. Published in Climate of the Past Discussion: 18 April 2012, URL: http://www.clim-past-discuss.net/8/1301/2012/; accessed in Feb., 2013.

A simulation of the last millennium is compared to a recent spatio-temporal reconstruction of summer temperature over Europe. The focus is on the response to solar forcing over the pre-industrial era. Although the correlation between solar forcing and the reconstruction remains small, the spatial regression over solar forcing shows statistically significant regions. The meridional pattern of this regression is found to be similar in the model and in the reconstruction. This pattern exhibits a large warming over Northern and Mediterranean Europe and a lesser amplitude response over Central and Eastern Europe. The mechanisms explaining this pattern in the simulation are mainly related to evapotranspiration fluxes. It is shown that the evapotranspiration is larger in summer over Central and Eastern Europe when solar forcing increases, while it decreases over the Mediterranean area. The explanation for the evapotranspiration increase over Central and Eastern Europe is found in the increase of winter precipitation there, leading to a soil moisture increase in spring. As a consequence, the evapotranspiration is larger in summer, which leads to an increase in cloud cover over this region, reducing the surface shortwave flux there and leading to less warming. Over the Mediterranean area, the surface shortwave flux increases with solar forcing, the soil becomes dryer and the evapotranspiration is reduced in summer leading to a larger increase in temperature. This effect appears to be overestimated in the model as compared to the reconstruction. Finally, the warming of Northern Europe is related to the albedo feedback due to sea-ice cover retreat with increasing solar forcing.

URL: http://www.clim-past.net/8/1487/2012/cp-8-1487-2012.pdf

13043976 Wu, J. Y. (Nanjing Normal University, College of Geography Science, Nanjing, China); Wang, Y. J.; Cheng, H.; Kong, X. G. and Liu, D. B. Stable isotope and trace element investigation of two contemporaneous annually-laminated stalagmites from northeastern China surrounding the "8.2 ka event": Climate of the Past, 8(5), p. 1497-1507, illus. incl. 1 table, sketch map, 62 ref., 2012. Part of special issue no. 47, Advances in understanding and applying speleothem climate proxies, edited by Mangini, A., et al., URL: http://www.clim-past.net/special_issue47.html; published in Climate of the Past Discussion: 3 May 2012, URL: http://www.clim-past-discuss.net/8/1591/2012/cpd-8-1591-2012.html; accessed in Feb., 2013.

The prominent "8.2 ka event" was well documented in the Greenland ice cores. It remains unclear, however, about its duration, structure and forcing mechanism at low- to mid-latitude regions. Here we use the physical and geochemical data of stalagmites from the Nuanhe Cave in Liaoning Province, northeastern China, to reconstruct a detailed history of East Asian monsoons covering the entire duration of the event. High-resolution chronologies of two contemporaneous stalagmites, each consisting of at least 770 yr annual growth bands, were established by calibrating and anchoring the floating band-counting ages against five high-precision ²³⁰Th dates. Two oxygen isotope profiles replicate each other on annual-decadal timescales despite their difference in growth rates, indicating that the d¹⁸O variability has a climatic origin largely associated with changes in the rainfall d¹⁸O from the West Pacific during summer season. A signal from the "8.2 ka event" was faint in our d¹⁸O records, not as significant as Indian monsoon dominated stalagmite d¹⁸O records from Qunf in Oman and Dongge in Southern China. However, our d¹³C and Ba/Ca profiles, as indicators of local environmental changes, provide strong support for a climate reversal centred at 8.2 ka BP, which is likely controlled by winter monsoon circulations via the westerly winds associated with North Atlantic climate. Therefore, we concluded that the winter- and summer-Asian monsoons responded independently to the high northern latitude climate.

URL: http://www.clim-past.net/8/1497/2012/cp-8-1497-2012.pdf

13042830 Zak, K. (Academy of Sciences of the Czech Republic, Institute of Geology, Prague, Czech Republic); Richter, D. K.; Filippi, M.; Zivor, R.; Deininger, M.; Mangini, A. and Scholz, D. Coarsely crystalline cryogenic cave carbonate; a new archive to estimate the last glacial minimum permafrost depth in Central Europe: Climate of the Past, 8(6), p. 1821-1837, illus. incl. sects., 3 tables, sketch map, 109 ref., 2012. Includes supplement, URL: http://www.clim-past.net/8/1821/2012/cp-8-1821-2012-supplement.pdf; part of special issue no. 47, Advances in understanding and applying speleothem climate proxies edited by Mangini, A., et al., URL: http://www.clim-past.net/special_issue47.html; published in Climate of the Past Discussion: 14 June 2012, URL: http://www.clim-past-discuss.net/8/2145/2012/cpd-8-2145-2012.html; accessed in Jan., 2013.

Cryogenic cave carbonate (CCC) represents a specific type of speleothem whose precipitation is triggered by freezing of mineralized karst water. Coarsely crystalline CCC, which formed during slow freezing of water in cave pools, has been reported from 20 Central European caves located in Germany, the Czech Republic, Slovakia and Poland. All these caves are situated in an area which was glacier-free during the Weichselian. Whereas the formation of usual types of speleothems in caves of this region usually ceased during the glacials, coarsely crystalline CCC precipitation was restricted to glacial periods. Since this carbonate type represents a novel, useful paleoclimate proxy, data from its Weichselian occurrences in caves in Central Europe were collected, including their C and O stable isotope values, U-series ages and depth below the surface. When using only the CCC data from caves with limited cave ventilation, the permafrost depths of the Weichselian can be estimated to be at least 65 m in the lowlands and uplands. An isolated CCC find indicates that Weichselian permafrost penetrated to a depth of at least 285 m in the High Tatra mountains, Slovakia. A model of the formation of coarsely crystalline CCC assumes its formation especially during periods of permafrost thawing. U-series data confirm that permafrost depth changed and CCC precipitation in deep caves occurred repeatedly in the studied area during marine isotope stages 4, 3 and 2. One important phase of coarsely crystalline CCC formation related to permafrost thawing occurred between 40 and 21 ka BP, and the last phase of its formation was related to the final permafrost destruction between 17 and 12 ka BP.

URL: http://www.clim-past.net/8/1821/2012/cp-8-1821-2012.pdf

13039335 Desyatkin, R. V. (Russian Academy of Sciences, Siberian Branch, Institute of Biological Problems of the Cryolithozone, Yakutsk, Russian Federation); Lesovaya, S. N.; Okoneshnikova, M. V. and Zaitseva, T. S. Palevye (pale) soils of central Yakutia; genetic specificity, properties, and classification: Eurasian Soil Science, 44(12), p. 1304-1314, illus., 19 ref., December 2011. Based on Publisher-supplied data; original Russian text; Desyatkin, R. V., et. al., 2011, published in Pochvovedenie, Vol. 2011, No. 12, pp. 1425-1435.

Permafrost-affected palevye (pale) soils of Central Yakutia are developed from mantle calcareous deposits of different textures and are characterized by the common mica-chloritic association of clay minerals with a higher content of chlorite in comparison with the soils developed from mantle loams and loess-like loams in the European part of Russia. In the pale soils, the distribution of clay minerals in the profile has an even pattern in the loamy variants and a differentiated pattern typical of podzols in the loamy sandy variants. Data on the chemical extracts and Mössbauer spectroscopy indicate that the iron in the pale soils is mainly fixed in silicate minerals. The content of nonsilicate iron represented by the amorphous and weakly crystallized compounds in the pale soils is relatively low. The humus-accumulative horizon in these soils is close to the gray-humus (soddy) AY horizon according to its acid-base characteristics (the soil pH and the degree of base saturation) despite the presence of exchangeable sodium and the shallow occurrence of the calcareous horizon. Copyright 2011 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229311120027

13037310 Kanev, V. V. (Russian Academy of Sciences, Institute of Biology, Komi Research Center, Syktyvkar, Russian Federation). Dynamics of acid-soluble iron compounds in Soddy-podzolic soils of the southern Komi Republic: Eurasian Soil Science, 44(11), p. 1201-1214, illus., 53 ref., November 2011. Based on Publisher-supplied data; original Russian text; Kanev, V. V., 2011, published in Pochvovedenie, Vol. 2011, No. 11, pp. 1312-1326.

The content of total iron and its contents in the Tamm, Mehra-Jackson, and 1 N H₂SO₄ extracts were determined for arable and forest soddy-podzolic soils with different degrees of gleyzation. The seasonal dynamics of the acid-soluble iron compounds in the soils were studied. It was found that the amount of iron extractable by 1 N H₂SO₄ was smaller than that passing into the Tamm and Mehra-Jackson solutions. The seasonal variation of the acid-soluble iron compounds in the humid years was significantly higher than in the dry years; it depended on the hydrological conditions of the year of observations and the soil density and degree of gleyzation. The temperature conditions of the year of observations had a lower effect on the content of the acid-soluble iron. The profile distributions of the acid-soluble and total iron depended on the vertical and lateral migration of water, as well as the meso- and microrelief conditions. An increase in the content of acid-soluble iron was observed under the decreased temperature in the spring and fall. The mobilization of iron under the effect of podzolization was activated during the period of the summer rains. In the third year of the agricultural development, the content of acid-soluble iron in the soils slightly decreased, which could be indicative of a decrease in the content of iron involved in the biological cycle under the development and drainage conditions. An exception was provided by the arable soils on the toeslope, where the content of acid-soluble iron was higher than that in the forest soils occupying analogous positions in the relief. Copyright 2011 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229311050073

13040553 Pereverzev, V. N. (Russian Academy of Sciences, Avrorin Polar-Alpine Botanical Garden-Institute, Apatity, Russian Federation); Kazakov, L. A. and Chamin, V. A. Genetic features of soils on marine sands and their windblown derivatives on the White Sea coast (the Kola Peninsula): Eurasian Soil Science, 44(1), p. 13-21, 4 tables, 21 ref., January 2011.

The Quaternary deposits on the Tersk coast of the White Sea are represented by marine deposits (the Tersk sands) enriched in the sea-sorted eluvium of the red Tersk sandstone. These deposits and the soils developed from them are characterized by the predominance of the fine sand fraction and the absence of gravel and the coarser fractions. The sediments derived from the red Tersk sandstone have an impoverished chemical composition (the silica content reaches 75-80%). The iron-illuvial podzols developed from them are characterized by the slightly pronounced differentiation of the main oxides and by the eluvial-illuvial redistribution of the amorphous Al and Fe compounds. Sandy soils-psammozems-with undifferentiated soil profiles are developed from windblown sands subjected to afforestation and from coastal marine sands under a relatively thin natural plant cover. Iron-illuvial podzols buried under a thin sand layer preserve the Al-Fe-humus type of the profile differentiation. In the recently deposited sand layer, the eluvial-illuvial redistribution of the chemical elements is absent. Copyright 2011 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229311010108

13040558 Vasil'evskaya, V. D. (Moscow State University, Faculty of Soil Science, Moscow, Russian Federation); Grigor'ev, V. Ya.; Pogozhev, E. Yu. and Pogozheva, E. A. Experimentally substantiated equations of the interrelations between the agrochemical characteristics of Tundra soils: Eurasian Soil Science, 44(1), p. 81-91, illus. incl. 4 tables, 16 ref., January 2011.

The detailed analysis of the results obtained in the course of experimental studying of the tundra soils in Western and Central Siberia and in the European part of Russia has revealed the general regularities of the variability and the relationships between the agrochemical and other properties of the soils. On the basis of these data, the calculated methods for the assessment of a complex of agrochemical properties of natural and disturbed tundra soils under different moisture and thermal conditions were elaborated. Among the properties analyzed, the following are important for plant growth: the acidity and the content of humus, organic carbon, total nitrogen, mobile phosphorus, nitrogen, and potassium. The relationships between the soil agro-chemical properties and the plant productivity allowed applying them for the quantitative evaluation of the environmental threat of the soil-plant cover's degradation because of different predominantly mechanical disturbances. Copyright 2011 Pleiades Publishing, Ltd.

DOI: 10.1134/S1064229311010157

13043635 Audry, Stéphane (Université de Toulouse, Observatoire Midi Pyrénées, Toulouse, France); Pokrovsky, Oleg S.; Shirokova, Liudmila S.; Kirpotin, Sergei N. and Dupré, Bernard. Organic matter mineralization and trace element post-depositional redistribution in western Siberia thermokarst lake sediments: Biogeosciences, 8(11), p. 3341-3358, illus. incl. 5 tables, sketch map, 93 ref., 2011. Published in Biogeosciences Discussion: 30 August 2011, URL: http://www.biogeosciences-discuss.net/8/8845/2011/bgd-8-8845-2011.html; accessed in Sept., 2012.

This study reports the very first results on high-resolution sampling of sediments and their porewaters from three thermokarst (thaw) lakes representing different stages of ecosystem development located within the Nadym-Pur interfluve of the Western Siberia plain. Up to present time, the lake sediments of this and other permafrost-affected regions remain unexplored regarding their biogeochemical behavior. The aim of this study was to (i) document the early diagenesic processes in order to assess their impact on the organic carbon stored in the underlying permafrost, and (ii) characterize the post-depositional redistribution of trace elements and their impact on the water column. The estimated organic carbon (OC) stock in thermokarst lake sediments of 14±2 kg m^-2 is low compared to that reported for peat soils from the same region and denotes intense organic matter (OM) mineralization. Mineralization of OM in the thermokarst lake sediments proceeds under anoxic conditions in all the three lakes. In the course of the lake development, a shift in mineralization pathways from nitrate and sulfate to Fe- and Mn-oxyhydroxides as the main terminal electron acceptors in the early diagenetic reactions was suggested. This shift was likely promoted by the diagenetic consumption of nitrate and sulfate and their gradual depletion in the water column due to progressively decreasing frozen peat lixiviation occurring at the lake's borders. Trace elements were mobilized from host phases (OM and Fe- and Mn-oxyhydroxides) and partly sequestered in the sediment in the form of authigenic Fe-sulfides. Arsenic and Sb cycling was also closely linked to that of OM and Fe- and Mn-oxyhydroxides. Shallow diagenetic enrichment of particulate Sb was observed in the less mature stages. As a result of authigenic sulfide precipitation, the sediments of the early stage of ecosystem development were a sink for water column Cu, Zn, Cd, Pb and Sb. In contrast, at all stages of ecosystem development, the sediments were a source of dissolved Co, Ni and As to the water column. However, the concentrations of these trace elements remained low in the bottom waters, indicating that sorption processes on Fe-bounding particles and/or large-size organo-mineral colloids could mitigate the impact of post-depositional redistribution of toxic elements on the water column.

URL: http://www.biogeosciences.net/8/3341/2011/bg-8-3341-2011.pdf

13040700 Painter, Thomas H. (Jet Propulsion Laboratory, Pasadena, CA); Deems, Jeffrey S.; Belnap, Jayne; Hamlet, Alan F.; Landry, Christopher C. and Udall, Bradley. Response of Colorado River runoff to dust radiative forcing in snow: Proceedings of the National Academy of Sciences of the United States of America, 107(40), p. 17125-17130, illus. incl. sketch map, 55 ref., October 5, 2010. Supplemental information/data is available in the online version of this article.

The waters of the Colorado River serve 27 million people in seven states and two countries but are overallocated by more than 10% of the river's historical mean. Climate models project runoff losses of 7-20% from the basin in this century due to human-induced climate change. Recent work has shown however that by the late 1800s, decades prior to allocation of the river's runoff in the 1920s, a fivefold increase in dust loading from anthropogenically disturbed soils in the southwest United States was already decreasing snow albedo and shortening the duration of snow cover by several weeks. The degree to which this increase in radiative forcing by dust in snow has affected timing and magnitude of runoff from the Upper Colorado River Basin (UCRB) is unknown. Hereweuse the Variable Infiltration Capacity model with postdisturbance and predisturbance impacts of dust on albedo to estimate the impact on runoff from the UCRB across 1916-2003. We find that peak runoff at Lees Ferry, Arizona has occurred on average 3 wk earlier under heavier dust loading and that increases in evapotranspiration from earlier exposure of vegetation and soils decreases annual runoff by more than 1.0 billion cubic meters or ~5% of the annual average. The potential to reduce dust loading through surface stabilization in the deserts and restore more persistent snow cover, slow runoff, and increase water resources in the UCRB may represent an important mitigation opportunity to reduce system management tensions and regional impacts of climate change.

DOI: 10.1073/pnas.0913139107

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13041432 Zhang, Xiaolei (Universite du Quebec, Institut National de la Recherche Scientifique, Quebec City, PQ, Canada); Yan, Song; Tyagi, R. D.; Surampalli, Rao Y. and Zhang, Tian C. Greenhouse gases emissions from natural systems; mechanisms and control strategies: in Climate change modeling, mitigation, and adaptation (Surampalli, Rao Y., editor; et al.), American Socciety of Civil Engineers, Reston, VA, p. 667-694, illus., 132 ref., 2013.

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13042370 Evans, Andrew (Metropolitan State College of Denver, Department of Earth and Atmospheric Sciences, Denver, CO); Janke, Jason R. and Hill, April A. Geochemistry of frost affected soil, Rocky Mountain National Park, Colorado [abstr.]: in Geological Society of America, Rocky Mountain Section, 64th annual meeting, Abstracts with Programs - Geological Society of America, 44(6), p. 92, May 2012. Meeting: Geological Society of America, Rocky Mountain Section, 64th annual meeting, May 9-11, 2012, Albuquerque, NM.

The nutrient movement in frost affected tundra soils can influence high altitude plant communities and alter the trophic status of alpine lakes and streams. To evaluate the geochemistry of soil pore water in tundra soils, intact soil core samples were collected in Rocky Mountain National Park, Colorado. Core samples were kept frozen at -5°C until use, at which time the cores were warmed to 18°C. Columns were leached with low ionic strength water, and leachates were collected using a fraction collector. Leachates were analyzed for Ca, Mg, K, Na, Cu, Zn, Mn, SO₄^2-, PO₄^3-, pH, and LMWOA. After leaching, the columns were drained, and frozen at -5°C for five days. Six sequential freeze thaw cycles (FTC) were used, the first three cycles involved a thaw, leach, drain, freeze cycle (-5°C, 5 days), the last three cycles involved thaw, leach, saturated column, freeze cycle (-5°C, 5 days). Leachate analysis showed that P leaching was correlated to elevated Mn and oxalic acid concentration in solution. Release of P into solution may be attributed to the dissolution of the manganese oxide solid phases adsorbing P, and competitive adsorption of P and oxalate for surface adsorption sites resulting in P leaching. Eluent P and Mn concentration in leachates were observed to decrease for the drained FTC, and increase for the water saturated FTC. Copper and Zn were leached from the columns with metal concentrations being influenced by the water content of the FTC. Magnesium leachate concentration decreased during the saturated FTC, while Ca showed no definite leaching pattern for either freeze thaw-cycle. Chemical speciation of collected leachates indicated considerable metal complexation with oxalate, with Cu-oxalate complexes ranging from 4 to 62% of total Cu, and Zn-oxalate complexes ranging from 4 to 21% of total Zn. The extent of metal-oxalate complexation correlated with oxalic acid concentration in the leachates. The identification and quantification of aqueous complexes can be used to elucidate the mechanisms by which P is released and transported in tundra soils.

13042321 Karlstrom, Eric T. (California State University Stanislaus). Range of mean annual temperatures of the past-million years inferred from properties of relict Paleosols and periglacial features, Glacier Park area, Montana [abstr.]: in Geological Society of America, Rocky Mountain Section, 64th annual meeting, Abstracts with Programs - Geological Society of America, 44(6), p. 84, May 2012. Meeting: Geological Society of America, Rocky Mountain Section, 64th annual meeting, May 9-11, 2012, Albuquerque, NM.

Particular kinds of soils and periglacial features form under particular climatic regimes. Thus, magnitude of past climate fluctuations can be estimated in areas where these features record environmental conditions significantly different from those of the present. Relict interglacial paleosols (less than a million years old based on paleomagnetic analyses) near Glacier National Park, Montana resemble fersiallitic soils (Paleudalfs, Palustalfs, and Paleudolls) of the southeastern U.S., where mean annual temperature (MAT) is at least 6 to 8°C warmer and mean average precipitation (MAP) is at least 40 cm greater than present climate in the Glacier Park area, where MAT is 4.2°C and MAP is 50 cm. Relict periglacial features in this area, including ice-wedge casts, record radically colder glacial conditions. Because active ice-wedges form in continuous permafrost where MAT is -6°C or less, their occurrence here suggests MAT in this area during full glacial conditions was at least 10°C colder than today. Thus, these data suggest that over the past ~ one million years, MAT fluctuated between -6°C or colder during full glacial conditions to 10 to 12°C or warmer during interglacials. Distribution of plant and animal fossils in mid-continental Eurasia and North America record a similar (extreme) range of average annual temperatures (at least 16-18°C or 29-32°F).

13042227 Porter, Courtney (University of Arizona, Hydrology and Water Resources, Tucson, AZ); McIntosh, Jennifer; Derry, Louis A.; Meixner, Thomas; Chorover, Jon; Rasmussen, Craig; Brooks, Paul D. and Perdrial, Julia N. Determining solute inputs to soil and stream waters in a seasonally snow-covered mountain catchment in northern New Mexico using Ge/Si and 87Sr/86Sr ratios [abstr.]: in Geological Society of America, Rocky Mountain Section, 64th annual meeting, Abstracts with Programs - Geological Society of America, 44(6), p. 67, May 2012. Meeting: Geological Society of America, Rocky Mountain Section, 64th annual meeting, May 9-11, 2012, Albuquerque, NM.

The "critical zone" is an open system where interacting biological, chemical, and physical processes contribute to long-term evolution of the Earth's surface and the structure of life on Earth. Mineral weathering is an important process in the "critical zone", which produces base cations that are essential nutrients to support the biotic foundation of ecosystems. This study investigates how changes in hydrologic conditions affect subsurface flowpaths, thereby altering weathering influences on stream chemistry in a seasonally snow-covered headwater catchment in the Jemez Mountains in northern New Mexico. Germanium/silicon ratios, Sr isotope ratios, major ions and dissolved carbon species are utilized to trace base cation cycling in the catchment. Major cations display chemostatic behavior despite fluctuations in the hydrograph implying that subsurface flowpaths are the dominant influence on streamwater composition. Major ion concentrations in streamwaters are most comparable to groundwater. Silicon, calcium, and sodium are prevalent in streams, consistent with plagioclase weathering. Low ion concentrations in precipitation and direct runoff would result in a dilution trend that is not observed. Therefore, solute fluxes are governed by equilibrium with primary and secondary minerals, and the rate at which solutes are transported by water out of the system.

13042776 Andreev, A. A. (University of Cologne, Institute of Geology and Mineralogy, Cologne, Germany); Morozova, E.; Fedorov, G.; Schirrmeister, L.; Bobrov, A. A.; Kienast, F. and Schwamborn, G. Postglacial vegetation history of central Chukotka deduced from permafrost paleoenvironmental records of the El'gygytgyn impact crater [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 34, 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13042778 Astakhov, Valery (Saint Petersburg University, Geological Faculty, St. Petersburg, Russian Federation). Postglacial Pleistocene of Russian Arctic mainland; an overview [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 36-37, 12 ref., 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13042786 Dorechkina, D. E. (Saint Petersburg State Mining University, St. Petersburg, Russian Federation) and Rekant, P. V. The distribution of late Quaternary glacial-marine deposit on the northernmost part of Novaya Zemlya shelf [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 46, 5 ref., 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13042818 Schirrmeister, L. (Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany); Wetterich, S.; Herzschuh, U.; Schneider, A.; Bobrov, A.; Tumskoy, V.; Kokhanova, L.; Zhukova, E.; Pestryakova, L.; Pfeiffer, E. M.; Kutzbach, L.; Beermann, F.; Joosten, H.; Teltewskaja, A.; Subetto, D. and Sitalo, V. Polygons in tundra wetlands; state and dynamics under climate variability in polar regions (POLYGON) [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 86, illus. incl. sketch map, 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13042827 Streletskaya, Irina (Lomonosov Moscow State University, Geographical Faculty, Moscow, Russian Federation) and Vasiliev, Alexander. The ice complex of Yenisey gulf coasts, Russia [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 95-96, 5 ref., 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13042823 Vasiliev, Alexander (Russian Academy of Sciences, Earth Cryosphere Institute, Tyumen, Russian Federation) and Rekant, Pavel. Interpretation of statistics of offshore permafrost table position [abstr.]: in APEX VI; Arctic palaeoclimate and its extremes; international conference and workshop (Immonen, Ninna, editor; et al.), University of Oulu, Oulu, Finland, p. 91, 2012. WWW. Meeting: APEX VI, May 15-18, 2012, Oulanka, Finland.

URL: http://www.apex.geo.su.se/images/pdf_files/apex6_abstracts_final.pdf

13041781 Albrecht, Christian (Justus-Liebig-University, Institute of Soil Science and Soil Conservation, Giessen, Germany) and Kühn, Peter. Properties and formation of black soils on the Island of Poel (NE Germany): in Black soils and black sediments; archives of landscape evolution (Faust, Dominik, editor; et al.), Quaternary International, 243(2), p. 305-312, sects., 4 tables, geol. sketch maps, 58 ref., October 26, 2011. Meeting: International workshop on Black soils and black sediments; archives of landscape evolution; distribution, formation, degradation, and properties, May 3-5, 2009, Dresden, Germany.

Recent soil mapping on the Island of Poel, situated in the southern Baltic Sea, shows an abundance of Black Soils developed in stratified parent material, whereby the upper layers are of periglacial origin covering calcareous till. The Black Soils have been formed in the upper layer overlying Luvisols, developed in decalcified till, with different degrees of stagnic influence. The Luvisols are not the result of a degradation of the Black Soil, as no humic clay coatings were detected in their Bt horizons. With a simplified Ap, Ah, (Eb/Ah), (2)E, 2Bt(g)b, C horizon sequence, these soils differ from the better known degraded Phaeozems on Fehmarn and the Uckermark region. The properties of three pedons are presented and their pedogenesis is discussed. AMS ¹⁴C ages from soil organic carbon of the Ah horizons from the Black Soils suggest that the development of the Luvisols stopped within the first half of the Subatlantic period. Abstract Copyright (2011) Elsevier, B.V.

DOI: 10.1016/j.quaint.2011.03.022

13041782 Andreeva, D. B. (Russian Academy of Sciences, Institute of General and Experimental Biology, Buryatia, Russian Federation); Leiber, K.; Glaser, B.; Hambach, U.; Erbajeva, M.; Chimitdorgieva, G. D.; Tashak, V. and Zech, W. Genesis and properties of black soils in Buryatia, southeastern Siberia, Russia: in Black soils and black sediments; archives of landscape evolution (Faust, Dominik, editor; et al.), Quaternary International, 243(2), p. 313-326, illus. incl. sects., 5 tables, geol. sketch maps, 79 ref., October 26, 2011. Meeting: International workshop on Black soils and black sediments; archives of landscape evolution; distribution, formation, degradation, and properties, May 3-5, 2009, Dresden, Germany.

Soils with deep and dark brown to black humic surface horizons, derived from sandy-silty aeolian and alluvial sediments, are relatively fertile and store huge amounts of carbon. Globally, they mainly correlate with steppe ecosystems. Because their deep and dark epipedons are frequently rich in Black Carbon, it was recently suggested that they developed due to prevalent burning of the semiarid vegetation. This paper describes six soils with deep and dark humic surface horizons, located in catchments of the Selenga and Uda rivers in Buryatia, southeastern semiarid Siberia. The organic matter of most of these soils not only originates from grass steppe, but in addition from trees and shrubs. Five soils can be classified as Chernozems and Kastanozems (WRB, 2006); one soil is a deep and black Anthrosol, occurring in patches in the region. All soils have calcic horizons below the mollic epipedon, some with cambic Bw horizons in between. As the parent material does not contain carbonates, aeolian input and hydrolysis of Ca-silicates contribute to the development of the secondary carbonate accumulation, which is frequently cryoturbated. All profiles are more or less stratified due to solifluction. Texture ratios (<6.3/63-2000 mm) show maxima in the dark A horizons, indicating advanced paedogenesis. This is supported by weathering proxies, including SiO₂/Al₂O₃ and Al₂O₃ ´ 100/Al₂O₃ + Na₂O. Increased concentrations of TiO₂, MgO and Fe₂O₃ presumably indicate advanced formation of chlorite. Radiocarbon analyses indicate that these deep and dark mollic horizons started to develop during the more humid-Holocene Climatic Optimum, ca. 7000-5000 BP. Palynological studies confirm expansion of forests in the Lake Baikal region in this period. This is in agreement with higher alkane ratios nC27/nC31 in most of the deep and dark A horizons, indicating that these epipedons, diagnostic for Chernozems and Kastanozems, did not develop exclusively under grass steppe, thus supporting the hypothesis that a significant part of the soil organic matter is inherited from trees and shrubs. This seems to be in contrast to Middle Europe and the Russian plain where Chernozems presumably developed during the early and mid-Holocene under grass steppe and subsequent degraded with increasing humidity and invasion of forests. High contents of Black Carbon in the Calcic Chernozem P4 and lower ones in the long-lasting occupied Hortic Anthrosol indicate that the deep and dark A horizons of Mollisols most likely do not result from frequent burning, but from biochemical processes. Abstract Copyright (2011) Elsevier, B.V.

DOI: 10.1016/j.quaint.2010.12.017

13043676 Curry, B. Brandon (Illinois State Geological Survey, Quaternary Geology Section, Champaign, IL). Forensic reconstruction of sediments and environments at the termini of prairie ice streams [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 485, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

In the south-central area once covered by the Laurentide Ice Sheet, the locations of prairie ice stream margins are clearly demarcated by long, broadly arcuate terminal and interlobate moraines. Deposits attributed to single advances (advance plus retreat deposits) range in thickness from more than 35 to less than 3 m. In Illinois, the hummocky terrain that typifies morainic areas shows little or no evidence of sediment stacking, faulting, or other features suggestive of compressive flow. Ice-walled lake plains (IWLPs) are locally common in the chaotic topography, especially in areas of sublobe interference where flow paths were short, and sediment relatively thick. IWLPs are formed largely of fossiliferous, 1-8 m thick successions of rhythmically bedded silts and very-fine sand. Fossils include ostracode valves, pillclams shells, chirominid head capsules, and the leaves, stems, buds, etc., of terrestrial and aquatic plants. The full IWLP record from Illinois indicate that from ca. 21,800 to 20,800 and 18,000 to 16,800 cal yr BP, newly-formed dead-ice permafrost supported shrubs with prostate growth habits, indicating cold, windy conditions. The intervening hiatus (ca. 20,800 to 18,000 cal yr BP) is indicated by the distribution of ages from IWLPs throughout Illinois, as well as by a paraconformity sandwiched by well-dated fossiliferous, laminated sediment. The paraconformity probably represents summer temperatures that were too cold to support a lake, as well as temporary inactivity of the active layer. Notably absent from the fossil record are trees and vertebrates, although these elements are locally abundant in kettle-fills near or abutting against ice-walled lake plains. The difference in age of the IWLP shrub fossils and kettle needles approximates the span of time when topographic inversion occurred from the onset of local deglaciation to full melting of the dead-ice permafrost.

13039505 Letsinger, Sally L. (Indiana University, Center for Geospatial Data Analysis, Bloomington, IN); Prentice, Michael L.; Olyphant, Greg A. and Riddle, Alexander D. Three-dimensional groundwater flow modeling using a geologic framework model of near-surface glacial sequences; northeastern Indiana [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 560, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

We describe the integration of a three-dimensional (3-D) geologic framework model (GFM) with a 3-D numerical, variably-saturated, groundwater-flow model. This project is part of ongoing research through the Great Lakes Geologic Mapping Coalition to provide detailed information about the 3-D distribution of subsurface sediments in glacial basins. Preliminary results of transient groundwater-flow simulations during periods of precipitation-driven recharge are presented. This project focuses on the Huntertown aquifer system in Allen County, Indiana, which is located within the northwestern flank of Erie Lobe moraines. The main aquifer is contained within the Pleistocene Huntertown Formation, which is composed of glaciofluvial and glaciolacustrine facies interbedded with loamy till. A previously constructed 3-D GFM of the Huntertown Formation was built by constructing georeferenced raster data sets representing the morphology of each major bounding surface. The upper boundary of the model is the ground surface and the bottom of the model is the overconsolidated till of the Trafalgar Formation (Pleistocene). Because we are working in depths less than 200 feet (60 meters), we were able to employ new information from detailed borehole data and seismic-reflection surveys to refine our depiction of the hydrogeologically important Lagro Formation, a mud-rich till that caps the aquifer sequence. Refinements to the upper part of the GFM that represents the Lagro Formation (Pleistocene) include numerous sand and gravel units within and below the till. Transient flow simulations were undertaken for the study area using the GFM. Soil and land-cover data provided spatially distributed bases for parameterizing the top surface of the model. Model outputs were processed to map areas of upward and downward near-surface flow, allowing us to identify areas of potential groundwater recharge and discharge. Locations of potential recharge and discharge are controlled by a combination of geologic materials and topographic variables. We review our methods of gleaning important information from numerical models to inform decision makers about aquifer sensitivity and vulnerability to contamination.

13039430 Niebuhr, Spencer R. (University of Minnesota-Minneapolis, Department of Earth Sciences, Polar Geospatial Center, Minneapolis, MN); Herried, Bradley; Obryk, Maceij and Doran, Peter. Projecting lake-level rise from airborne lidar and climate models in Taylor Valley, Antarctica [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 407, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

The McMurdo Dry Valleys (approximately 77°45'S, 162°E) is the largest ice-free valley system in Antarctica with a cold, hyper-arid climate. Despite extreme polar conditions, isolated biological communities are present in valley soils, lakes, and streams and are sensitive to even small changes in climate and environmental conditions. Taylor Valley is the southernmost of three large east-west valleys and it contains three large, closed basins with perennially ice-covered lakes (Lake Bonney, Lake Hoare, and Lake Fryxell). Lake levels are rising (increasing water volume rates ranging from ~140,000 m³/year to ~2,200,000 m³/year) due to an imbalance in ablation (sublimation and evaporation) rates and input of liquid water. We modeled lake-level change in Taylor Valley using current regional climate models to quantify hydrological change. We merged a LiDAR-derived digital elevation model (DEM) of Taylor Valley (2 meter resolution) with a bathymetric grid of each lake (2 meter resolution), resulting in a hydrologically-sound elevation model of the Taylor Valley floor. Volumes were then calculated at one meter elevation intervals to produce a hypsometric curve for each lake basin. From the hypsometric curve, we used past and present measured lake levels and current climate models for Taylor Valley to calculate volumetric rise for each basin. The climate model supports ten-year averages in lake-level rise at a constant rate, accounting for average observed flood years. We then used the hypsometric curve to extrapolate a function which projects yearly water volumes for each basin. The final results allowed us to determine when the basins will merge and spill into the adjacent Ross Sea. Basin spill events have implications on the fragile, isolated biological communities as well as the geologic landscape. The high spatial resolution of the DEM resulted in more accurate calculations of future shoreline locations and water volume than ever previously measured. This study, more generally, shows an application of LiDAR data, bathymetric data, and climate models to understand closed-basin processes in unique climatic environments.

13039523 Rice, Karen C. (U. S. Geological Survey, Charlottesville, VA); Deviney, Frank A.; Cosby, Bernard J. and Lynch, Jason. Understanding sulfate dynamics in unglaciated Eastern U.S. catchments [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 564, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

Several decades of acidic atmospheric deposition have affected the quality of eastern U.S. stream water. Sulfate, derived from acid rain, is the primary acidifying component deposited in surface waters. The Clean Air Act legislation and amendments have gone far in reducing sulfate deposition to Earth's surface. Studies of trends in sulfate concentrations in surface waters in the northeast have shown declines in sulfate concentration accompanying the declines in sulfate deposition. Stream sulfate concentrations in the Mid-Atlantic and southeast, however, have shown no significant change. The common explanation for the lack of response in streams in the Mid-Atlantic and southeast is that sulfate deposited from the atmosphere is adsorbed onto clay minerals in soils and retained in the catchment. Long-term sulfate input/output budgets for catchments in the region are needed to test this hypothesis. To conduct such a sulfate input/output budget analysis, we searched for sites with simultaneous monitoring of stream discharge and sulfate concentrations and for which estimates of dry and wet deposition are available. We compiled data from long-term studies of forested catchment streams in the Eastern U.S. south of the line of glaciation, from northern Pennsylvania to northern Georgia along the spine of the Appalachian Mountains. We analyzed stream discharge and sulfate concentrations in 34 catchments, with records at some sites as long as 35 years. Estimates of wet deposition were derived from the National Atmospheric Deposition Program and extrapolated to each of the 34 sites. Dry deposition estimates were derived from U.S. EPA's CMAQ model for each site. Although the biogeochemical budgets of several of the individual catchments have been analyzed extensively, this study presents the first regional analysis of the sulfate budgets for all 34 catchments. Our analysis demonstrates that over the period of record for this data set, atmospheric deposition has exceeded stream export in most cases, supporting the hypothesis that catchment soils in this region are strong retainers of sulfate.

13039482 Walter Anthony, Katey (University of Alaska-Fairbanks, Water and Environmental Research Center, Fairbanks, AK). Regional scale variability in methane emissions from thermokarst lakes [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 556, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

The relationship between thermokarst (permafrost thaw) and methane emissions from lakes and wetlands has been investigated at relatively few sites around the Arctic with highly variable results. The goal of this paper is to explore the relationship between soil and peat carbon inputs to lakes via thermokarst erosion and methane emissions from lakes in order to explain regional-scale variability in methane emissions. Ground-based surveys of biogenic methane ebullition seeps in 75 lakes along a North-South transect in Alaska revealed that the majority of lakes emit methane via ebullition; however, geographic differences in permafrost, soil organic matter, climate and geology result in large (>10-fold) regional differences in lake methane production and emission on a lake-area basis. Thermokarst lakes that formed in icy, organic-rich Pleistocene-aged yedoma-type permafrost, common in previously unglaciated regions of Alaska, had the highest methane emissions. Erosion of Holocene-aged peat into thermokarst lakes formed in polygonal tundra had lower methane emissions. Non-thermokarst lakes had among the lowest levels of methane emissions. Radiocarbon ages of lake methane reflected the age of soil carbon inputs to thermokarst lakes. These results have implications for using knowledge of soil carbon storage and erosion for upscaling lake methane emissions in the Arctic.

13041783 Zech, Michael (University of Bayreuth, Department of Soil Physics, Bayreuth, Germany); Leiber, Katharina; Zech, Wolfgang; Poetsch, Thomas and Hemp, Andreas. Late Quaternary soil genesis and vegetation history on the northern slopes of Mt. Kilimanjaro, East Africa: in Black soils and black sediments; archives of landscape evolution (Faust, Dominik, editor; et al.), Quaternary International, 243(2), p. 327-336, illus. incl. strat. cols., 4 tables, geol. sketch maps, 57 ref., October 26, 2011. Meeting: International workshop on Black soils and black sediments; archives of landscape evolution; distribution, formation, degradation, and properties, May 3-5, 2009, Dresden, Germany.

This study presents numerical dating and geochemical results obtained for a soil transect on the northern slopes of Mt. Kilimanjaro, East Africa. Accordingly, the investigated soils in the montane forest zone comprise Late Quaternary palaeosol-sequences, which are characterised by inverted weathering profiles. This can be explained through the aeolian accumulation of unweathered volcanic dust that is provided by katabatic winds from uncovered periglacial hillsides since at least 28 ka cal. BP. Several proxies (C/N, d¹³C, d¹⁵N and alkane biomarkers) provide evidence for vegetation changes during the Late Quaternary. Strikingly, an expansion of savannah or alpine C4 grasses as on nearby Mt. Kenya cannot be confirmed. However, C3 grasses expanded remarkably at 2600 m a.s.l. during the last glacial maximum and montane forest communities replaced the ericaceous/grassy communities during the Early Holocene. Abstract Copyright (2011) Elsevier, B.V.

DOI: 10.1016/j.quaint.2011.05.020

13041941 Zhang Mingyi (Chinese Academy of Sciences, State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions, Lanzhou, China) and Harbor, Jonathan M. Modeling the thermal behavior of highly porous media embankments in permafrost regions [abstr.]: in Geological Society of America, 2011 annual meeting, Abstracts with Programs - Geological Society of America, 43(5), p. 416-417, October 2011. Meeting: Geological Society of America, 2011 annual meeting, Oct. 9-12, 2011, Minneapolis, MN.

Embankments for road and rail support in permafrost regions are typically made to be highly porous as part of efforts to ensure their long-term thermal stability. Examples include many important road and rail engineering projects, including the Qinghai-Tibet Railway and Highway in China, the Alaska Highway in the USA and the Baikal-Amur Railway in Russia. Typical construction methods include interlayer embankments, revetment embankments and U-shaped (interlayer and revetment) embankments. The cooling effects of highly porous media embankments made from crushed rocks or cinderblocks have been evaluated previously using numerical simulation, laboratory tests and in-situ observation. Thermal models have used a variety of approaches to characterize flow in highly porous media, including Darcy and non-Darcy porous media models as well as a block model based on fluid-solid coupled heat transfer theories. Here we present the results of modeling work designed to evaluate the behavior of novel designs intended to increase the thermal stability of an expressway with a wide and high-temperature upper surface. This includes composite highly porous media embankment structures such as crushed-rock interlayer embankments with ventilated ducts, hollow concrete brick (cinderblock) embankments combined with ventilated ducts, and an embankment with an L-shaped thermosyphon and crushed-rock revetment. This work is designed to advance understanding of thermal interactions between built structures and permafrost, and to provide the basis for new road and rail embankment engineering in permafrost regions. Additional work focuses on simulating thermal behavior of embankment in permafrost regions under conditions likely to result from global warming.

13041805 Anfinson, O. A. (University of Calgary, Calgary, AB, Canada) and Leier, A. L. U-Pb geochronology and U-Th/He thermochronology applied to the clastic strata of the Franklinian Basin, Canadian Arctic Islands: in 2011 CSPG CSEG CWLS conference; abstract archive, CSPG CWLS Conference, 2011, 3 p., 4 ref., 2011. Meeting: 2011 CSPG CSEG CWLS conference, May 9-11, 2011, Calgary, AB, Canada.

The statistical data are provided on the vertical electric sounding of the thickness and specific electric resistance of permafrost ground in the region of the joint between the east slope of the Polar Urals and the West Siberian Plain.

URL: http://www.cspg.org/documents/Conventions/Archives/Annual/2011/225-U-Pb_Geochron ...

13038201 Kniesel, Christof (University of Würzburg, Institute of Geography and Geology, Wurzburg, Germany); Rödder, Tobias; Roth, Nils and Schwindt, Daniel. Electrical resistivity monitoring for the detection of changes in mountain permafrost at different time scales: in Geoelectric monitoring; current research and perspectives for the future; book of extended abstracts (Supper, Robert, prefacer), Berichte der Geologischen Bundesanstalt, 93, p. 51-56, illus. incl. 1 table, 9 ref., 2011. Meeting: GELMON 2011; 1st international workshop on Geoelectric monitoring, Nov. 30-Dec. 2, 2011, Vienna, Austria.

13038202 Ottowitz, David (Geological Survey of Austria, Department of Geophysics, Vienna, Austria); Jochum, Birgit; Supper, Robert; Römer, Alexander; Pfeiler, Stefan and Keuschnig, Markus. Permafrost monitoring at Mölltaler Glacier and Magnetköpfl: in Geoelectric monitoring; current research and perspectives for the future; book of extended abstracts (Supper, Robert, prefacer), Berichte der Geologischen Bundesanstalt, 93, p. 57-64, illus. incl. sketch map, 5 ref., 2011. Meeting: GELMON 2011; 1st international workshop on Geoelectric monitoring, Nov. 30-Dec. 2, 2011, Vienna, Austria.

13038225 Rode, Matthias (Karl Franzens University of Graz, Institute for Geography and Regional Sciences, Graz, Austria) and Sass, Oliver. Monitoring of water content, water displacement and freeze-thaw processes in alpine rock walls using geoelectric survey lines: in Geoelectric monitoring; current research and perspectives for the future; book of extended abstracts (Supper, Robert, prefacer), Berichte der Geologischen Bundesanstalt, 93, p. 204-211, illus. incl. sketch map, 15 ref., 2011. Meeting: GELMON 2011; 1st international workshop on Geoelectric monitoring, Nov. 30-Dec. 2, 2011, Vienna, Austria.

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